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How do I translate Universal Time into my time?

The Earth has 24 time zones. This article explains how to translate UTC to your local time zone.

The world is divided up into about 24 time zones. We say about because some states, regions or countries shift their times by half an hour from the strict 24 hour divisions. Standard time within most time zones is an integral number of hours offset from a time scale called Coordinated Universal Time (abbreviated UTC), maintained by a large number of very precise “atomic clocks” at laboratories around the world, including the U.S. Naval Observatory. For nontechnical purposes, we can presume that Coordinated Universal Time (UTC) is the same as Greenwich Meridian Time (GMT), although their exact definitions differ.

Let’s say you live in Houston, Texas, which is in Central Standard Time (U.S.). To convert 18 UTC into your local time, subtract 6 hours, to get 12 CST. During daylight saving (summer) time, you would only subtract 5 hours, so 18 UTC would convert to 13 CDT.

Or, let’s say you’re in Paris, France, which is in Central European Time. To convert 18 UTC into your local time, add 1 hour, to get 19 CET. In summer, add 2 hours to get 20 CEST.

When converting zone time to or from UTC, dates must be properly taken into account. For example, 10 March at 02 UTC is the same as 9 March at 21 EST (U.S.).

The table can also be used to determine the difference between the time observed in any two zones. For example, the table shows that Eastern Standard Time is three hours ahead of Pacific Standard Time (U.S.).

Bottom line: The Earth has 24 time zones, but when astronomers mention a time, it’s often “Universal Time.” This article explains how to translate Universal Time, or UTC, to your local time zone.